Photovoltaic solar power systems often employ a means to adjust the photovoltaic module tilt with respect to a horizontal plane in response to changes in sun position throughout the day. This is done by adjusting the photovoltaic module tilt angle continuously or at frequent intervals to maximize the total radiant flux striking the active module surfaces, thereby maximizing plant electric output and financial revenue.
A common and effective design technique to achieve this end is the single axis tracking mount configuration for larger scale photovoltaic power generation facilities. This technique typically employs rows of multiple modules fixed in a common plane to a rotatable shaft, whose axis of rotation is usually oriented along a horizontal, north/south axis. An integral drive mechanism enables rotational adjustment of the shaft and thereby the tilt angle of the attached modules in each row throughout the day to maximize power production.
The target tilt angle in these designs is often calculated using generally accepted sun position algorithms based on astronomical calculations for the location of interest to determine the tilt angle from horizontal of a plane containing both the rotational axis of the tracking mechanisms and the center of the sun. Such an alignment technique typically minimizes the angle of incidence of direct beam solar irradiance striking a perpendicular to the front surface of the modules.
The figures depict various embodiments of this disclosure for purposes of illustration only. One skilled in the art can readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein can be employed without departing from the principles of the invention described herein.